SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd4361aa925b94cc951aac1054de16a29c3ff1d4e9e4306e74e2759f4ea8e237b' 
  AND token = '+DHxXKqJGY4zyZvy9xpIlm5xCkjR6WO0icvf5wkygnY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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