SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd37954333d120b8636240b552ff03e51b857e16fa8a42f63555d7fbc74425f9' 
  AND token = 'cQZpsqrH6P7ZHUIHG1RI+MBAYaKGAQQWPnu7heBSIQA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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