SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62e15374b8939d53683c0a62dd7b2c24fb4107216efd514082d12bea9f88ff64' 
  AND token = '/m/hq4q6C+lp0ZSRO4y1MGhqxkiLUKqp28Z/jCZcSVc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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