SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5092bd352fc59f07ebd731a5b063ac05f2cd0b61874aae01cdcc8959c4a027b1' 
  AND token = 'B/1Ia5xLG7+WPzkzhLY8ptfPRqyS/M2PXdTyXGn2cZ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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