SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2d17c2de0f774a2ee214fcfb4dfb848057f6aa6dcf5de3877a8b1f79e00b9204' 
  AND token = '9LLDCJ/2vUsVpCyRkBkI71dRTGK/Uqyipp5I3hYEhQw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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