SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc8523b997adfd525d1b5c01b6892985915674fd0637f446d7557b2914c4f72a' 
  AND token = 'nw80kND/t8po3b+lgb2Ec6qnmL9gFqJLUCOJcQcJAMg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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