SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1aca4871966465acca8fb6017e175546dbf70bef774de7f201f2578a12f674d9' 
  AND token = '08qpFIz/ZH+2XYGQrS/ueVMcATE+gDIL0R9tiWFKOVU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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