Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8b1c91d1f2a0b609d04afccb3588dbc73bfac535d4bfe4d28a5d03abe3931500' 
  AND token = 'DodJGDGcJIdfLlrgUgVqyHgQ1+2inbnGyzofrjbDgAk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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