SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '28614af37cfe52542e08ded4f7277064a545cdf44c486ba22f3bf3bf264c99db' 
  AND token = 'SIeWuGfd3W3P1wqu1PdqdQvCFUOQCVnOQE0m/0MgOio=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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