SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b024a0a448c3a8d9c8472a5492903bfab6cbb4a4e1c7e626a055fad5479dab70' 
  AND token = '7gi/iR5/uiJI0HGBJhKvBLC2Ssuuv/dGEauOP3Q3ajU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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