SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '16aa95325f7acbfae8ac4d202c51e4e65ca3dfd8135692241bb2d8d1ef25f1d5' 
  AND token = 'HMgvSAneCAOu5LWNzdZZVJTUtWf7Qnerou8wKgLOp4w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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