SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'acfd6fdb95815a26f3e83ef2df86fca140a823e21b708e95f7535525be13f9bd' 
  AND token = 'mcSVpMWrl8KkvCxR0Q0lqzw6+A+L9JXYqyuFhWZyJL0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00010

JSON explain

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