SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7acb76751c7b14114be7063ff935c3ed6242efc540af088592739d17c8b3f055' 
  AND token = 'NBMNqnKRXvcq8e+6QhYvZ7ql9hVuL6Sm5+idnJhg77A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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