SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a418ddfadc0ebc6dcd1aeddc726c256467226294a3ccac847e1dad28118c571' 
  AND token = 'GE4+fhlJUnrROhtX2OkYKuTZKp9Fhe5//lqacEhPHgs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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