SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '225ea6cbe2056758667b0cc99c3024d2fada61131f413041436b03dc6476f4f7' 
  AND token = 'jaoxeucrvDpgv81shhkGnm9Nr7xgKz7zA25q2xwksDg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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