SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5075988d7cdf39bfc640b65490d2ee7278ce1970e7706c3d8f5236b61e709335' 
  AND token = 'nxYAnUC7eGct/Peu2uCrJd4AGWj6nw1DFKFq+UqW+M8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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