SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '19dc60c7a50cdfbb8f439919d9d9e3867beed57fe6692526d508cbd770852044' 
  AND token = 'zXqtuPMB7p5JlJXbKVO+mALLVUKmWK5Fu7I/ZlTGuTc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}