SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ef7e1d56e0760aaa20f59f32f711279e25ddc4f3ba0b720439a21b1dd718da1a' 
  AND token = 'izeMfktyOpoBEQLvbtTmSU+pCAjo1IDreBKMK+eLPWY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}