SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '009b5ba544eff2d61c7e00a50127f692f4fabbcdd3eedde7d584791f03c49c6a' 
  AND token = 'zFYol/qUPS+L4gGBlJy6u8FlJB1LbyMzH8yq787RZSI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}