SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ecab98962fefc46c9ddd496c35ed41533ed058c129a4fec72b2c4d0f7dc16daf' 
  AND token = 'tRhKf8/tMyAfPoEIhSFjfqRgLeC3qJVJwrCmusWZjSE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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