SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2aa0d4fb8891db0d398853cbdfd092da2408508c159ff9ea5c3a548dbb5fe97' 
  AND token = 'qPyltEkVfiaMjx+YvzrZ6uT1c/4OCfNQJ/sFWqH0Bp0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00060

JSON explain

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