SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'df7177ac72658924e0c7458d4c12a265d25ad167081280f95477853bc56f056a' 
  AND token = 'to1414WuaI9onQKiQMOX2tqwm06U1w2NQjG0lN53gII=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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