SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd16b32c0f97742e8ce04fde392d2b59661d2b50f81aa356ace6edaa6de94cdd1' 
  AND token = 'MF3zpxXISl2G/egCOEYg9hrlQbMuI0RY+whSA5nvV+Q=' 
  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"
    }
  }
}