SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9554232188984dfcd7f8513ad3b22b217dbe9e09f24f66841582bce908bfb8fd' 
  AND token = 'qYQPOemct59TruOAHNYdxwtClvbI6xqcMHMJETDB6BU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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