SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b934511f1bc855d7d202315c07be4d15cc3abf85d9e4bced2468cd05efe20247' 
  AND token = 'VP9QeWDb7QucYPYjSqZJlwpw3XPK0nBwSGpjPaDIqKo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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