SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '24be5a551c9689d8708d32137f6056df62ed78165ac5ad3b55038a9870a8f58d' 
  AND token = 'Yahs4ifUbfbZirk1tWDOgKqw/Kei9C97LurldrPyYXQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00054

JSON explain

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