SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'f1c67a3f9bcdfec79508e524bd1f57bbc1f4c52f7385947e869e954e2e184dcd' 
  AND token = 'ri7ueeBLj2In+3Ogyw3qm8DQVPT/psgokLAwKXKGiwQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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