SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '99dc42c572dcfd1213cb8329300d08cbdf1bc7102403ff89fabb006b8f965c58' 
  AND token = 'FEXu0TpydaaXVoi99A/wRSV3IMUtrEgRKLYNFY0Feos=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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