SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8afe3f19b3fcd0644e0eb41494139977f13aff8485b16f24f7a732d65797b844' 
  AND token = 'mvZC72AgSbT4jEN6OKK4xyM2RdLr7nqVzUHmmgzNYfA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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