SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ecb5b64e14075908c46c382e1a77d2f850673b208bef80285bfd210aa4851abb' 
  AND token = 'Ewwo7IoCqfvdMc+VQ2I1GhJj6fjBtitN7yfp9DXPsqQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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