Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '128b521bd38d22f3bc103df8a90603d04de364cff33973e2c2aad94bde4488b2' 
  AND token = '5XCtAjO04olzImpwrj9UJOIWzTEWUCr5UInfiV2HAR0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}