SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f8716788694944ba9998dd286182cc374572d9a893ce8639a3f695bc7c2ebb24' 
  AND token = 'CfUqwhTfDfFiN2V3RWNZk04Z+cyrry9R/u0NHXSIVlE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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