SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '031edfaa9f6c963a64a9f4edded5ffd382dcadf8b53d3cf2a74f702ba215c6b7' 
  AND token = 'lqE7tx1envKRqbUzCEq5k7XaR8pLdqbDiKMSuabdKz8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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