SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a31be3746d4171931e399bba3af1de7a9fcc2044f2ddd9fee6bc2df87064b8ea' 
  AND token = 'y6t0zd4O2z22go0x42l1NLiv18qIllttqkfESSP87Zc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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