SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '166dce58b3a26d8ca76845ac7cdaa986076ebc12e915faee66bdb30f7baabbb9' 
  AND token = 'XNVce1RbvQs/kpR1kbbFCTdiO9OhRa2cWxoz3oQxpAg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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