SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'adac20994f7124521cf7f63e43d0095137289901d4098c5342f90680ee6acc95' 
  AND token = 'ayNikpaYKARVqoGo8GVzCxsFgHMX1jjrI7B9/4lmnQU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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