SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '863cef7ca391c782c23dee6ce3414e7970be106aed94e7195baabe484404103c' 
  AND token = 'wOd2e3+f5Br8QvNLNA6/+1kvwZzKMd4ObJaetu25ExI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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