SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4c5ba9fed37eb734cf88792761f1488bbc226471f2bcb81e293bab14eccd3ad1' 
  AND token = 'IuzoO7knjkgfW5TUNvxQ//BAsiowU3mf+hS6l5VT10E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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