SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33c412517bcb2c84df7f3902b9c059efc3d44edc88100fd7d46d10da36354dc1' 
  AND token = 'z6ISnMcpeKv6JuedKSBiiraVaOIuiwMiIFs1B2HuN/I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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