SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3087bb75c0d5b8f9dfefce676591a67eb315d8a1fc39be7c467d94b154e0678a' 
  AND token = 'EH2YFs2EZsSNUpmXhaD0qzviMfYvA0ssrD8TX7NZyM0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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