SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '18a50136fa78c24c5dc60324998b379979149273bcb9933f84f9c24ccec0448f' 
  AND token = 'nA++Gd3+lCbqiDXT+evGznULSuq6p8gqI+V2SHHnjOM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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