SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '2f0b07617c137cbae9d4a9abac16e47396dc42c0e95d4d8dec0c832b16b4dc88' 
  AND token = '4DBSOIIEaUTD2A+sVPTlDZLZvhSKKcNzq0aGt8xLRBg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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