SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e60563e004a8d72eddc74754a252c1b745e226c92d2e3f8a45bb7dc70dee2c78' 
  AND token = 'SVzsRXV5U9bAaD+lhwZIeUYxBfevC+1xaMOWrCwNm6Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00084

JSON explain

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