SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5dfed8e9632edb6bf5e793e9ef16874773beaaffd1026bdf396fe5bd47136ea9' 
  AND token = 'Y4dv7OZ/af098V6dGOYfaxwrGV1E46CmmaUWDIsQpdY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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