SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '93183f942fa01ab0a950e39cd0a91234f8a76f328453b7b7a868fb0179c79b42' 
  AND token = 'Pp4idHyuGWKw+Fq7gLB5gWDYjmbaYRxMnGArrq7DKmY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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