SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25710d69828068a8075c2c6a4bdddf8a9446567a5ab7a1c57885052f561ee804' 
  AND token = 'bl6r8uT1AOobbAM/igdOP8RDI3pFLK6OLwoigi4snSc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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