SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3d22686ead2d2dc4b170fbc2d0bd416d95848421fe35a9fbd598521ffa8dbab8' 
  AND token = '2Df2pY0Wr2wdk/DMjwGOUi3Y9PHFulcVcuCjRFMRwrk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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