SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4c7520d5fdc69f772cee8b2aeca5436ada336adfd7643b894ef2df42269586db' 
  AND token = 'zoCtFQp2d6xo6LmTNglhvWUvTy8TeWO67TKlKcQL+xE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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