SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f6af4a58c2cfe6fffcb55b5171df53e783d6736c59ac5627d3ddf83ed4e02ad1' 
  AND token = 'ByfNTtOR+GsKLBSAXaxPBXsUKkYXRj6yuGO2IqJO4Rg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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