SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '69f82e6a183856e9a91ba7077eea445b89f007949e8489db0bc059bcd41f492d' 
  AND token = '2NfPRCNhMUJYzdDEtli/sXDSOXoMI5cdVDnhIlcih0s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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