SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f05f2d3a93b2411116a8882e3b0a7c175cabcc875bcf2af1df8a4bde56622df' 
  AND token = '9DfWUSS+tVHUTayNqZohe4cNsijjamlCtyVuMhDwzWY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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