SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a1c0ce81536647e4598ee3171874a4328dbd426c7af2e6aa8ccc5b43ac18d61b' 
  AND token = 'lk//9VabhA+3+c9QTrpNMA2c5jBd93pn4ZxpNlqpL58=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00139

JSON explain

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