SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a31594779666c1022655cf899b98131e770d4529b088e6b61292f36b1cb8523f' 
  AND token = 'NzhbfqCgnG4KTn0+BmTAJB3VpooyWcAcx4hKGdYN26w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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