SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f3756c996f4872a09b39a6f533ae62a151795fd473973db56d2ac98d61e0ce39' 
  AND token = 'PG6+ZRm4UHDUf3ld87UCZPMndKZganOfi68ZJx06pPg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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