SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc02c46d6f926cc9ac82b167cdff036309736b6e1259d8d30f61c11d81ddb89e' 
  AND token = 'EiHv7QHyDiopPDGKiCLrD+tNtEkoIuJH5wN2+TEfPH0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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