SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c188a59b4d94f171a2b7c6a4ed22f71ee28381509ae4b0ee7e66392752bd6821' 
  AND token = 'fd42X1WetNCCyG8VURSHWblHNxFIwg2RvNxFJim5ZF8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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