SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '7d9fe0edf37891e02c0b76ca48774319d2196245c11be6c12d2bf20e36a376f5' 
  AND token = 'oymRCSLGdqigp9BoxKPLhk8JtzYi7DONDcFDRNUQLMw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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