SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bbb25f2f50e2dc78ef40fb74471607e666486452eaaace80bb4bd49274cc19a8' 
  AND token = 'JOmwqgmv67Bm6rvQHWzVY8Xx7yLWSOlaXvOsQCI3Gqw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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