SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25207f091d4292d768d00bf18cd2dc1f4349520b529d86f430f7856d8f020a8e' 
  AND token = 'CZHp75SYzgnYEwsmGVfa/C27GRrmAb+k/a3sLpGTApU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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