SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '305d2929b301695e5c37980d680db7dab057fb5a57583ce854ee1e99ea775e29' 
  AND token = 'ZiEdB9Siq28OoF+31XYao5p9tVSab0ASRb/X/DMIXvk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}